1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Rom4ik [11]
3 years ago
7

The nearest star to Earth is Proxima Centauri, 4.3 light-years away.

Physics
1 answer:
PIT_PIT [208]3 years ago
7 0

Answer:

a) v = 2,152 10⁸ m / s   b)   t = 2.71 10⁸ s  or t =  85.93 year

Explanation:

a) In this special relativity exercise we have that time is measured in the same ship, so it is the proper time,

    v = d / t

Let's reduce the distance to the SI system

    d = 4.3 l and (9.46 1015 m / 1ly) = 40.678 10¹⁵ m

    t = 5.0 y (365 day / 1 y) (24 h / 1 day) (3600s / 1h) = 1.89 10⁸ s

Let's calculate

    v = 40.678 10¹⁵ / 1.89 10⁸

    v = 2,152 10⁸ m / s

b) The time seen from the ground for which the ship moves is given by

     t = t₀ / √ (1- (v/c)²)

Let's calculate

     t = 1.89 10⁸ / √ (1 - (2.152 / 2.998)²)

     t = 1.89 10⁸ / 0.6962

     t = 2.71 10⁸ s

Let's reduce this time to years

    t = 2.71 10⁸ s (1h / 3600s) (1day / 24h) (1 and / 365 d)

    t =  85.93 year

You might be interested in
A 1200-kg car initially at rest undergoes constant acceleration for 9.4 s, reaching a speed of 11 m/s. It then collides with a s
Natalka [10]

To solve this problem we will apply the principle of conservation of energy and the definition of kinematic energy as half the product between mass and squared velocity. So,

KE_i = KE_f

KE_f = \frac{1}{2} mv^2

Here,

m = Mass

V = Velocity

Replacing,

KE_f = \frac{1}{2} (12000)(11)^2

KE_f = 72600J

Therefore the  final kinetic energy of the two car system is 72.6kJ

8 0
3 years ago
an ice skater applies a horizontal force to a 20.-kilogram block on frictionless, level ice, causing the block to accelerate uni
stiv31 [10]
The only vertical forces are weight and normal force, and they balance since the surface is horizontal. The horizontal forces are the applied force (uppercase F) in the direction the block slides and the frictional force (lowercase f) in the opposite direction.

Apply Newton's 2nd Law in the horizontal direction:
ΣF = ma
F - f = ma
where f = µmg

F - µmg = ma
F = m(a +µg)
F = (20 kg)(1.4 m/s² + 0.28(9.8 m/s²)

F = 83 N
3 0
3 years ago
As the Moon orbits Earth, its direction constantly changes. Which of these forces is most likely causing this change in velocity
zysi [14]
Gravity is the most likely force causing this phenomenon. please leave a thanks
8 0
3 years ago
What is the average velocity of a car that travels 30 kilometers due wet in 0.50
rodikova [14]

Answer:

60km/hr west

Explanation:

When you are dealing with velocity you always name the direction its going in

3 0
3 years ago
When a condenser discharges electricity, the instantaneous rate of change of the voltage is proportional to the voltage in the c
e-lub [12.9K]

Answer:

460.52 s

Explanation:

Since the instantaneous rate of change of the voltage is proportional to the voltage in the condenser, we have that

dV/dt ∝ V

dV/dt = kV

separating the variables, we have

dV/V = kdt

integrating both sides, we have

∫dV/V = ∫kdt

㏑(V/V₀) = kt

V/V₀ = e^{kt}

Since the instantaneous rate of change of the voltage is -0.01 of the voltage dV/dt = -0.01V

Since dV/dt = kV

-0.01V = kV

k = -0.01

So, V/V₀ = e^{-0.01t}

V = V₀e^{-0.01t}

Given that the voltage decreases by 90 %, we have that the remaining voltage (100 % - 90%)V₀ = 10%V₀ = 0.1V₀

So, V = 0.1V₀

Thus

V = V₀e^{-0.01t}

0.1V₀ = V₀e^{-0.01t}

0.1V₀/V₀ = e^{-0.01t}

0.1 = e^{-0.01t}

to find the time, t it takes the voltage to decrease by 90%, we taking natural logarithm of both sides, we have

㏑(0.01) = -0.01t

So, t = ㏑(0.01)/-0.01

t = -4.6052/-0.01

t = 460.52 s

3 0
3 years ago
Other questions:
  • What happens to the saturation for when adding salt to water at room temperature
    11·1 answer
  • Do you think there are other planets outside of our solar system? Support your response with facts
    5·2 answers
  • Which of the following are metric units? gallons kilograms pounds inches
    14·2 answers
  • The graph below shows the displacement of an object as a constant
    14·1 answer
  • If a polar is swimming with an average of 2.6 m/s how far will it traveled after 120 seconds ?
    5·1 answer
  • A battery has a terminal voltage of 12.0 V when no current flows. Its internal resistance is 2.0 Ω. If a 4.6 Ω resistor is conne
    11·2 answers
  • An electron is released from rest in a weak electric field given by E,--2.50 x 10.10 N/C j. After the electron has traveled a ve
    7·1 answer
  • I will mark brainiest! Please help ASAP
    11·1 answer
  • A 10 ohm resistor has 5 a current in it. what is the voltage across the resistor?
    8·1 answer
  • Add these two velocity vectors to find the magnitude of their resultant vector.
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!